Fire Door Gap Size Allowances - Am I protected?

For me, it’s that time of year again, annual facility fire door inspections.  I already know that the majority of these doors are going to fail, primarily due to door gap size allowances being exceeded. Current codes, NFPA 80, requires a maximum door gap allowance of ⅛” around the top and vertical perimeters of a fire rated door.  They allow up to ¾” door gap allowance at the bottom perimeter of the door. 

As I walk through the facility with my tablet and door gap gauge, I have to be prepared for the litany of questions that I will inevitably receive from facility managers. The primary question being, “How do I know that gap measurement is sufficient?”

In March of 2018, the NFPA’s Fire Protection Research Foundation published a report to answer the question of how did the gap size allowances come to be, and are the current gap allowances the best practice. The study included a literature review of more than 100 published documents and media, and computer modeling.  This report, Influence of Gap Sizes around Swinging Doors with Builders Hardware on Fire and Smoke Development, can be viewed in its entirety.

This study and report made some of the following conclusions:

“From this information a great deal of information and data was collected that directly reveals that the gap sizes around swinging doors have a significant effect on the fire development.”

“A significant amount of work was done to trace the historic record of the prescriptive gaps sizes included in NFPA 80. It was revealed that the first inclusion of these gaps sizes was added in 1959. Initially, requirements were based on the mounting of doors; however, in 1967 the requirements switched to being based on the door construction. There is no evidence to suggest that this was done from a fire performance perspective, however the test reports from that time period indicate that the prescriptive gap sizes are in the vicinity of what was found during full scale testing.”

Aegis Fire Door Gap Gauge

Disability and Fire

Annually, an estimated 1,700 residential building fires involving individuals with mental disabilities are reported to U.S. fire departments and cause an estimated 85 deaths, 250 injuries, and $61 million in total loss.  Additionally, there are an estimated 700 residential building fires involving individuals with physical disabilities that occur each year, resulting in 160 deaths, 200 injuries, and $26 million in property loss.

According to the reports, the majority of the residential building fires involving individuals with mental (62 percent) and physical (63 percent) disabilities occur in one- and two-family dwellings.  Cooking, at 22 percent, is the leading cause of residential fires where a physical disability is reported as a human factor contributing to the ignition of the fire.  This differs from the leading cause of residential fires where a mental disability is reported as a human factor contributing to ignition.  In these types of fires, intentional is the leading fire cause, at 40 percent.  Fire incidence involving individuals with disabilities occur most often in January and December.  In addition, these fires show a tendency to peak in the late afternoon to early evening hours.

The USFA has released the following two topical reports on residential building fires involving individuals with disabilities.

1. Residential Building Fires Involving Individuals With Mental Disabilities
2. Residential Building Fires Involving Individuals With Physical Disabilities